Core for use in molding concrete walls.



G. CLARK. CCEE ECR USE IN MCLDINC CONCRETE WALLS.

A APPLICATION FILED 0011s. 1910. 1,077,952.

Patented Nov. 4, 1913.

ri lu h 'MKM UNITED STATES PATENT OFFICE.

GEORGE CLARK, 0F LANDSBOROUGH, VICTORIA, AUSTRALIA, ASSIGNOR TO ALFRED HENRY STANBROUGH, TRADING AS MONO SIT CONCRETE COMPANY, OF RICH- MON D, AUSTRALIA.

CORE FOR USE IN MOLDING CONCRETE WALLS.

Specification of Letters Patent.

Patented Nov. 4, 1913.

Application filed Detober 15, 1910. Serial No. 587,254.

To all whom t may concern:

Be it known that I, GEORGE CLARK, a subject of the King of Great Britain, forlnerly` residing at Gordon street, Elsternwick, but now residing at Landsborough, in the State of Victoria, Australia, architect, have invented a Core for Use in Molding Concrete Walls, of which the following is a specification. j

This invent-ion relates to improvements in cores for use in molding concrete walls and it proposes a core of collapsible nature which may be readily set up or collapsed and associated with or removed from the molding apparatus.

The invention is illustrated by the accompanying drawings whereof Figure` l is a view showing in side elevation and longitudinal` section a preferred form of the improved collapsible core. Fig. 2 is a transverse sectional view of the mold and the core. Fig. 3 is a plan View of the complete mold as shown in Fig. l. In this figureone of the cores is shown in horizontal section. Fig. 4L is a horizontal sectional view (viewed upward) of the core expanded in which the dotted lines indicate the position of the links thereof when the lower end of the core is contracted.

.The molding apparatus shown comprises mold planks C, C, adapted to be set on edge face to face at the required distance apart. These planks are provided near their lower edges and on their inner or adjacent sides with laterally projecting pins C, which after the first course is molded rest on the preceding course of concrete, such as B and while temporarily supporting the planks constitute the gage for the height of each course. By this means the lower portion C2 of the planks below the pins C operlap the previously molded course of concrete on the outside.

The planks are clamped to form the mold by devices which include vertical ribs a. arranged opposite each other and placed against the outside of the respective planks. Each rib of the pair extends above the top edges of the planks and is connected to the other by a compression rod adjusted by means of nuts engaging the threaded ends of said rod which pass through holes in the ribs a. By adjusting the length of the compression rod between the ribs, the grip of the clamping device may be regulated. A draw bar H is passed through slots formed in the vertical ribs at about the height of the course of concrete to be molded. Said bar is conf nected at one end by a pin H to one rib and is provided at its other end with a cam lever Z adapted to bear against a preferably flattened portion of the other rib. By operating said lever the ribs a, a, are drawn toward eachother and the planks are clamped against the top of the course of concrete below such as B. Hopper boards E, provided with notches E which fit over the draw bars, are placed on the top of the planks and the concrete is filled in and tamped to the level of the planks, after which the hopper boards are removed and the concrete struck or leveled with the top of the planks. The draw bars H are each provided on one side with a socket c and on the other side with two clips or lugs The collapsible core F which forms the subject of the present invention comprises a beveled cap piece 71) from which depend hinged flat ribbed sides g extending down below and inside the top of the last course of concrete, while curved corner pieces p provided at the junctions of the sides also depend from said cap piece. The cap piece has internally two cross ribs h2 from which depend a pair of internal stays z' of T-section provided at the lower end with a slotted cross head A central spindle k provided with a handle Z passes through the boss h of the cap piece and the cross head y' and is provided at its lower end with a circular flange m. Pivoted to said flange are four arms n', n2, the latter being preferably curved, connected by links n, to the lower ends of the corner pieces p, while two n of said links have studs o engaging the slots j in the cross head y' and adapted to slide along same. By turning the central spindle 7c through the medium of its handle Z, the links are eX- panded as in full lines, Fig. 4, and contracted by reversing the spindle as in dotted lines, thus causing the core to collapse toward the lower end into an approximately taper or wedge shape, which facilitates its withdrawal from the concrete whether in a plastic or set condition. The cap piece L is secured in position by a lug r on one end which fits into the socket c on the draw bar of the clamping device7 while on the other end are corner lugs s which rest on the clips or lugs f of the adjacent draw bar. ln using this apparatus after a Certain section of one course of concrete is completed, the cores, are collapsed and reinoved after which the clamping ydevices and niold planks are displaced and erected ahead for another length of work and the cores replaced on the draw bars and expanded again when the process of filling and taniping is continued and so on until one complete course around the building is, completed.

l clainit- Y ln apparatus for molding concrete walls n situ, a collapsible core comprising a beveled cap piece provided with a central bossand with lugs at one end and two corners, four sides and corner pieces hinged to saidv cap piece, two internal stays attached to trated in the drawings.

cross ribs on the latter and provided at 20 Vlatter engaging the respective slots n the cross head, and a series of links connecting said arms with the lower ends of the corner pieces substantially as set forth and as illus- 30 In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

GEGRGE CLARK.

Witnesses PHILIP VILLIAM MUST, HUGH GORDON Moinzow.

Copies of this patent vmay be obtained for five cents each, byaddressng the Commissioner of Batents,

'Washingtonl D. C. 

